<?php
/*
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
 */

namespace Doctrine\ORM\Query\AST;

/**
 * Abstract class of an AST node
 *
 * @license http://www.opensource.org/licenses/lgpl-license.php LGPL
 * @link    www.doctrine-project.org
 * @since   2.0
 * @version $Revision: 3938 $
 * @author  Guilherme Blanco <guilhermeblanco@hotmail.com>
 * @author  Jonathan Wage <jonwage@gmail.com>
 * @author  Roman Borschel <roman@code-factory.org>
 */
abstract class Node {
	/**
	 * Double-dispatch method, supposed to dispatch back to the walker.
	 * 
	 * Implementation is not mandatory for all nodes.
	 * 
	 * @param $walker
	 */
	public function dispatch($walker) {
		throw ASTException::noDispatchForNode( $this );
	}
	
	/**
	 * Dumps the AST Node into a string representation for information purpose only
	 *
	 * @return string
	 */
	public function __toString() {
		return $this->dump( $this );
	}
	
	public function dump($obj) {
		static $ident = 0;
		
		$str = '';
		
		if( $obj instanceof Node ) {
			$str .= get_class( $obj ) . '(' . PHP_EOL;
			$props = get_object_vars( $obj );
			
			foreach( $props as $name => $prop ) {
				$ident += 4;
				$str .= str_repeat( ' ', $ident ) . '"' . $name . '": ' . $this->dump( $prop ) . ',' . PHP_EOL;
				$ident -= 4;
			}
			
			$str .= str_repeat( ' ', $ident ) . ')';
		} else if( is_array( $obj ) ) {
			$ident += 4;
			$str .= 'array(';
			$some = false;
			
			foreach( $obj as $k => $v ) {
				$str .= PHP_EOL . str_repeat( ' ', $ident ) . '"' . $k . '" => ' . $this->dump( $v ) . ',';
				$some = true;
			}
			
			$ident -= 4;
			$str .= ($some ? PHP_EOL . str_repeat( ' ', $ident ) : '') . ')';
		} else if( is_object( $obj ) ) {
			$str .= 'instanceof(' . get_class( $obj ) . ')';
		} else {
			$str .= var_export( $obj, true );
		}
		
		return $str;
	}
}